A common optical connector is a multi-ferrule connector. Multi-ferrule connectors are used, for example, in a variety of applications. In particular, in the VMEbus International Trade Association (VITA) 66.1 Fiber-Optic Connectors for use with MT Ferrules system, the ability to achieve a high bandwidth connection utilizing a large number of ferrules in parallel is constrained due to the physical structure of components in the system. This connector system has been designed for use as independent or stand-alone connectors in ANSI/VITA 48.1 (air-cooling applications) and ANSI/VITA 48.2 (conduction-cooling applications) applied to printed wiring boards (PWBs)/plug-in units defined in ANSI/VITA 46.0 VPX systems. Typical applications are in the aerospace and defense industry and include use in adverse environments for Embedded Computing, Processing, Avionics and Vetronics, Radar, Secure Communications and Imaging/Targeting.
Generally, a multi-ferrule connector comprises a housing having a plurality of openings for receiving a plurality of ferrule assemblies. A ferrule assembly comprises a ferrule terminated with fibers, which extend rearwardly from the ferrule. The length of the fibers extending from the ferrule can vary from just a few inches to many yards. A multi-fiber connector also comprises a ferrule retainer behind the ferrules for preventing the ferrules from being pushed/pulled rearwardly and out of the openings in the housing. In other words, the ferrule retainer functions as a backstop for the ferrules. Generally, a ferrule retainer is a plate-like structure comprising a number of openings to accommodate the ferrule assembly fibers. The ferrule retainer also comprises accessways along the periphery of the retainer to each of the openings such that the fibers of each ferrule assembly can be slid through the accessway and into the opening from the side of the retainer as opposed to be threaded through the openings, which can be problematic for long lengths of fibers. Furthermore, after the distal end of the ferrule assembly fibers are spliced or otherwise terminated, it is impossible to thread them through the openings. See, for example, U.S. Pat. No. 9,507,098. Therefore, for all intents and purposes, to be commercially viable, the ferrule retainer must have accessways from its periphery to each of the ferrule retainer openings to accommodate installing the ferrule assembly fibers prior to assembling the ferrule retainer to the housing.
Applicants recognize that this conventional design tends to limit the configuration of multi-ferrule connectors. Specifically, the conventional design can only accommodate multi-ferrule connectors in which each ferrule retainer opening is along the periphery of the ferrule retainer to have access to the periphery of the retainer. In other words, the conventional design cannot accommodate a ferrule retainer with interior openings. As used herein, an interior opening in an opening in the housing or ferrule retainer that is not adjacent the periphery of a housing or ferrule retainer. For example, a multi-ferrule configuration having a 3×3 matrix (i.e., three rows and three columns) of ferrules defines one interior opening. Applicants recognize that the conventional design does not permit multi-ferrule configurations having one or more interior ferrules because providing access from the periphery of the ferrule retainer to the interior opening is difficult, if not impossible.
Accordingly, Applicants recognize the need for an improved design to increase the number of ferrules that a multi-ferrule connector can accommodate. The present invention fulfills this need among others.